Revenant
by DownToTheSea
Summary: A routine mission throws Nikola into a nightmarish loop of events as he and Helen discover an old threat has reappeared.
1. Spiral

**A/N: Set post-canon, roughly six months or so. Also contains temporary character death - it doesn't stick, but I just wanted to give a warning!**

* * *

"Nikola?"

Nikola was currently deep in thought about two things: how much power he needed to wheedle Helen into letting him divert from the abnormal levels for his latest experiment, and what he was going to get her for her upcoming birthday. One of the downsides to being immortal, he had learned, was that after a while you just ran out of gift ideas.

What he was not deep in thought about – what wasn't even crossing his mind in the slightest way at all, for that matter – was the conversation going on around him.

Helen's voice snapped him back to attention, and he glanced up at where she stood behind her desk. "Yes, my dearest?" he said, smiling innocently.

Helen rolled her eyes, giving that tiny exhale that meant she was having none of it at the moment. She gestured at Henry and Kate, who stood opposite her.

"Perhaps you'd care to go over the mission details again, for all of our benefit," she said pointedly.

"Sure." He got up, his hand automatically going to his hip as he grinned at the room at large. He was about to take a sip of wine from the glass in his other hand, but realized it was empty. He must have finished it off during his reverie earlier. Damn. He must be distracted, if the consumption of a fine vintage like that had gone unnoticed.

The conversation he wasn't paying attention to had been less a conversation and more Helen going over the specifics of tonight's mission with them all. Fortunately, he hadn't needed to listen, because Helen had told him most of the details already.

Two bodies had been found in as many days, torn to shreds in the city's warehouse district. It was always the warehouse district, Nikola mused – why didn't this stuff ever happen on a sunny beach?

At the same time, rumors had begun to spring up around Helen's contacts that there was a rare and dangerous abnormal (or a few dozen, depending on the reliability of the contact) that was hunting near there. They were vague about exactly where it was supposed to be, but the reports seemed to center around one of the larger buildings in the middle of the district.

They were off to investigate tonight. So Nikola knew everything he needed to know, and the rest of the Sanctuary did too. There was no reason to bore everyone by reciting repetitive information.

Nikola put the empty glass down on Helen's desk. "We're going to go in there," he told Henry and Kate very seriously, "and we're gonna kick ass."

Kate snickered and Henry gave a suspiciously timed cough as Helen sighed off to Nikola's side.

"Very helpful, Nikola, thank you," she said, though not without amusement. "Now, perhaps we should get going. None of my contacts have said exactly when this creature, if it exists, comes out to hunt, but I don't want to miss it."

Nikola leaned across her desk, catching her eyes in his. "What are we waiting for?"

* * *

"Henry, Kate, you head around back," Helen ordered, her voice barely a whisper. "We'll see if we can box it in before it realizes we're here."

"Sure thing, doc," Henry said. He and Kate hurried off. To their credit, they made hardly enough noise for even Nikola's hearing to pick up.

"You sure have them well-trained," Nikola muttered.

"Quiet," Helen said. "Whatever this creature is, it's most likely killed at least two people so far. I'd rather you didn't become the next."

He smiled. "Oh Helen, be careful. You don't want to embarrass the children with your passionate declarations of love for me."

Helen's lips twitched, but all she said was, "Follow me."

If whatever they were looking for really hunted here, Nikola didn't know where it was finding its prey. The place was deserted, and from the looks of things had been that way for a long time. A layer of dust several inches thick coated the sides of the halls, and every door they opened creaked like they were on an episode of Operation Paranormal, swinging forward on rusty hinges.

Every so often, a metallic clang sounded, bouncing off the walls so they couldn't determine its point of origin. It was probably just the old building making noise, as old buildings had a tendency to.

But these noises were getting closer.

Even Nikola was starting to get creeped out. "Nice place," he whispered. "Want to vacation here?"

Helen turned around to give him a look. Just then, there was a metallic screech from further down the corridor, as if somebody was dragging a particularly vicious set of nails down a chalkboard.

They halted abruptly and Helen raised her stunner, but a minute or two passed with no sign of movement anywhere around them. The noise stopped.

"Are you two alright?" Helen asked into her com, sounding unnaturally loud in the sudden silence.

Henry's voice crackled into their ears. "We're good, how about you guys?"

"We're fine. Have you found anything yet?"

"Not yet," he said. "What was that, anyway?"

"I don't know," Helen said, frowning.

"Ok, I'll say it. This place is spooky." Nikola stuck his hand out as Helen lowered her stunner. "Hold my hand?"

She shook her head, giving him another impressive eye roll. "Really, Nikola," she muttered.

He grinned as they started on their way again. As they walked, Helen extended her free hand behind her, wrapping her fingers around his. She looked behind her and gave him a little encouraging smile. Nikola blinked in surprise before squeezing her hand and nodding back.

That sound had rung a bell in Nikola's head, but he couldn't quite place it. He was still racking his brains when there was another faint but familiar noise, a distant rumbling, from one of the endless corridors ahead of them.

He stopped, taking Helen's arm. "Do you hear that?" he asked in a low voice.

Helen tilted her head, listening for a moment, but in the second she took to listen Nikola remembered what it was. He grabbed her waist and pulled them both as far to the side as he could before curling himself around Helen.

A wave of energy rippled past them almost as soon as they hit the side of the hallway. It missed them by a hair, but its force was still enough to press them both against the wall painfully hard. With it came a blast of heat that seared across Nikola's back. He held onto Helen tighter, trying to shield her.

In another moment, it was gone, and they both took a deep breath. Nikola let go of Helen, turning to face her.

"Are you alright?" he asked.

Helen nodded, stepping away from him. "I know that weapon," she said sharply.

"Yeah, so do I," Nikola said. "'Cause I built it."

Helen's eyes widened slightly before she shook her head. "Nikola, tell me the creature here isn't what I think it is."

He grimaced. "Sorry."

She slapped a hand up to her earpiece. "Henry, Kate, listen to me. You need to be careful – it's a vampire." She glanced at Nikola. "At least one. Not as strong as Nikola, but be on your guard."

There was no answer.

"Henry, Kate, can either of you hear me? Please respond." Helen's voice was growing louder as her worry set in. "Henry? Kate?"

After another few seconds of silence, Helen fixed Nikola with a blistering look. "You told me they were dead."

"I thought they were!" His heart rate had picked up, an uncomfortable certainty settling in the pit of his stomach. Even Henry didn't stand a chance against one of his vampires.

"It doesn't matter," she bit out. "Go find Henry and Kate, now."

Nikola stared at her for a moment. "No, I – I'm not leaving you."

"Nikola," Helen said dangerously. "Go. I'll be fine." She holstered her stunner, taking out her guns instead. "You're faster by yourself."

Before Nikola could argue any more, a figure hurtled at them out of a side passage, tackling him to the ground. Nikola threw his arms up to cover his face instinctively, his claws and fangs extending as he kicked up. He only hit thin air as the creature – the vampire – dodged him without a second thought, and Nikola dropped his arms, swiping his claws across its chest and digging in, about to twist it off of him.

But he'd left his head exposed, and before he could do anything more the vampire had its own claws buried in Nikola's neck. Nikola choked as it dragged its hand down his throat, cutting deep into his chest, and the burning pain made him lose his grip on it.

"Nikola!" Helen shouted, and he only had time to turn his head towards her before she fired both guns into the creature on top of him. Her shots sent it reeling off him, giving Nikola a chance to scramble to his feet. His neck was already healing.

She had redirected the vampire's attention to her, and it snarled, turning away from Nikola and flinging itself across the hall at her. Helen fired more rounds into it and shouted something that couldn't be heard over the sound of her gunfire, though Nikola knew Helen well enough to guess. It halted in its tracks for a moment, but her bullets weren't going to last forever.

Hissing, Nikola threw himself at it and went for its throat. His fangs were only millimeters away when it managed to wrench away from him, heaving him to the side. Nikola hit the wall with such force that he could feel a few bones break in the arm he'd flung out to take the impact, and the wall buckled slightly.

What the hell was going on with this thing? There was no way it should have been this strong. Nikola knew its limits, or had thought he did; he had created it. This was one of the vampires he had turned years ago underneath Rome as Helen watched. He had thought they were all dead – they should have been dead. John had killed the rest of them after he had teleported Helen away, and John wasn't one to leave something like that unfinished.

But he had left Nikola for dead too, and Nikola was still alive and kicking. John had really done a number on him, and Nikola could only vaguely remember his recovery. It was possible that one of the other vampires had escaped his notice.

It shouldn't have attacked him, either. It was hardwired to obey him – the thought of hurting him shouldn't have even entered its mind. But somehow, his control over it had been broken, and now he had no way short of killing it to stop it from giving into its ravenous blood lust.

For that matter, it shouldn't have been intelligent enough to salvage the Cabal's weapon and use it, which it most definitely had if earlier was anything to go by. And why had it taken so long to come out of the woodwork?

But however any of this had happened, the vampire was here now, and it was springing towards Helen again. Helen emptied the clip into it, giving Nikola enough time to grab it from behind, seizing it around the chest with both hands.

He hissed again and sent as strong an electrical current as he dared through both of them, his eyes turning black as the other vampire gave a cry of pain. After centuries of experiments, if there was one thing Nikola knew he was more resistant to than any other living thing on the planet, it was electricity.

Helen had reloaded, and she fired a single shot with pinpoint accuracy into the vampire's head. Its eyes went blank and it stopped struggling against him, and Nikola stepped back as it sank to the ground.

He took a deep gulp of breath, feeling the last of his wounds close up, and looked at Helen. She was uninjured – the vampire had never made it to her.

"That was hot," he said, and Helen rolled her eyes. "Thanks for the help, by the way."

She nodded back. "Likewise."

"Thank you, Helen. I've always thought I looked quite handsome as a vampire. It's these, I think," Nikola said, twirling one of his claws.

Helen sighed. "Is it going to stay down?"

Nikola looked at it, pursing his lips. "Huh. You know, I'm really not sure. I've never been shot in the head, so I don't really have a frame of reference. I suppose you don't happen to have any of your fun vampire-proof restraints on you, do you?"

"I, ah, didn't think to bring them," Helen said, a hard edge in her voice, and he knew they were about to start arguing about how he'd gotten them into this mess.

"Helen," he said. "I didn't know any of them had survived. I'm sorry, alright?"

"Just…go find the others," Helen said, sounding weary. Nikola felt his heart sink. He'd managed it yet again: he had disappointed her.

"Not without you," he insisted. The fight had driven them to a crossroads in the hall, with several passages opening up to each side, and he could hear their voices echoing through them.

"I'll slow you down. I'm not having this conversation with you again, Nikola, just _go_ alre-" Her words were cut off as something collided with her, blurring out of the shadowed hallway so quickly and quietly Nikola hadn't seen it coming.

Before either of them had time to react, the second vampire's claws had slashed through Helen's neck, drawing a strangled cry of pain from her as it bent its head closer to the flow of blood.

Nikola's eyes went wide, her name tearing from his throat as he threw himself at the other vampire, heedless of anything other than getting it away from her.

He dragged it off her even as she lifted one shaking hand to her neck, the other grasping her gun and firing. Her shot went wide and hit it in the shoulder, and Nikola felt the bullet graze him on its way through. But it was enough to distract the vampire long enough for Nikola to pull it farther away from Helen.

There was a guttural kind of cry coming from him that Nikola was barely aware he was making, and he gripped the vampire's neck, his claws driving into its skin, and poured a stronger current than even he could handle for very long through it. It stunned Nikola, but it accomplished its purpose: the other vampire fell to the floor, convulsing, before it lay still. Nikola swayed, blinking to clear his head.

 _Helen._ He darted over to her, nearly slipping in the pool of blood already forming on the ground. Falling to his knees beside her, he slid an arm under her back and lifted her, cradling her against him. Her hand had fallen away from her neck, lying limply off to the side and allowing the blood to flow unchecked. Nikola covered the wound himself, his unsteady hands barely working. Her eyes were closed.

"Helen." His voice trembled. "Helen. Wake up, Helen – please – "

Her eyes opened a little and she gave him a small, flickering smile.

"Helen." Relief flooded over him and he clutched her a little tighter. "Ok, just hold on," he said, his words spilling out in a rush. "I'll get you back to the Sanctuary, that great lug of a butler of yours can fix you up, you'll be fine. Just – just hold on."

He got his feet under him, preparing to lift Helen up, but she motioned him to stop, giving him a look.

"Nikola," she said gently.

All his relief dropped out from underneath him, his eyes widening in horror. The world seemed to tilt suddenly and violently on its axis.

"No," he choked. "No. No, no, please – You can't – you can't…" The rest of his words died in his throat.

"Find Henry and Kate," she told him, her voice barely audible. She touched Nikola's cheek, her hand slick with blood. "Look after them."

Nikola was shaking his head. His mind should have been racing to find a solution, to save her, but he was numb with terror. "No," he managed again, his voice breaking. He had to take a shuddering breath before he could speak. "Helen, please, Helen – Helen – "

Helen's eyes unfocused, looking off somewhere behind him, a new expression on her face: fear.

Nikola stared at her before swallowing. If there was nothing else he could do for her, at least he could make sure she wasn't alone. He willed his voice to stop quavering.

"It's alright, Helen." The lie came to him with startling ease, and he took her hand, entwining her cold fingers with his. "It's alright. I – I'll take care of the kids, I swear."

Helen nodded, her eyes closing again.

"Helen." Nikola stroked her hand with his thumb, tears filling his eyes. _Not yet_. "Helen, wake up."

She didn't answer.

* * *

Nikola lost track of how long he knelt there, still holding Helen's hand in his. His head was bowed, his forehead touching hers as he sobbed, tears sliding down his face onto her.

He should go find the kids. He'd promised Helen to keep them safe.

The force of his determination to keep that promise surprised him; it filled him with enough strength to scoop Helen up in his arms and stand, his legs trembling under him. He started walking, stumbling along blindly in the direction Henry and Kate should be. Only a few steps down the hall, he nearly tripped over one of the vampires' corpses.

 _His_ vampires. He had caused this – it was his fault, and his alone. Helen was gone because of his carelessness. Helen, extraordinary Helen, was dead, all because of him.

It struck Nikola like a physical blow, and he sank to his knees again, curling around Helen. The dark corridors around them were eerily silent now, the only audible sounds the apologies he choked out to Helen over and over again.

* * *

"Nikola?"

"Uh, yes, my dearest?" The words came out automatically. Nikola didn't even know where he had gotten the breath for them, since he felt like he'd just landed from a fall off a thirty-story building.

His eyes were fixed on Helen, standing behind her desk and giving him an annoyed look, and very much alive.


	2. Redux

**A/N: While this fic is set post-canon, Bigfoot is mentioned in this chapter (and will show up later) because I steadfastly refuse to believe he's dead in canon.**

* * *

"Perhaps you'd care to go over the mission details again, for all of our benefit," Helen said. The familiarity tugged at Nikola's mind, but he didn't care about anything right now except her.

"Helen," he breathed, staggering to his feet and lurching across the room. "Are you real?"

"Blimey," Helen said, chuckling. "Have you been distilling liquor in the lab again?"

Nikola stopped just short of Helen. When he tentatively reached out to touch her cheek, he found her skin warm and solid against his, reassuring him she was really alive. He melted into her, clutching her against him.

"Helen, you're alive." Nikola barely even heard himself through his haze of relief, repeatedly pressing kisses to as much of her as he could reach with his face buried in her shoulder.

Helen patted his back. "I'm fine. Are you feeling alright?"

"You're alive," he murmured. "Oh Helen, Helen…" He pulled her even closer, running his hands through her hair and across her back.

"Uh, should we leave you guys alone?" Kate asked, clearly somewhat amused by the whole thing.

Helen leaned back, gripping his shoulders and looking him in the eyes. "Nikola, tell me what's wrong."

"I – " He stepped away and tried to put himself together, steadying himself on Helen's desk and taking a deep breath. "Nothing. I'm fine."

Before the mission, what did he remember? He'd been up in the beautiful new lab Helen had built for him, doing computer updates with Henry for the majority of the day: impossibly boring work transferring the files Helen had managed to save from the old Sanctuary over into the new computers. He had almost welcomed the meeting right after that as a change of pace, even if he usually thought they were a waste of time. It had been interrupted almost as soon as it began with a phone update from Will from…wherever he was. Nikola had pretty much stopped paying attention to Will most of the time – in fact, he distinctly remembered that was when he had begun to tune out, contemplating his own private projects instead. He could easily have nodded off.

"It was a dream," he said, letting another wave of relief pour over him even though it didn't feel quite right. "That's all." He collapsed into his chair and threw back the remainder of the wine in his glass, thankful it wasn't empty this time.

"That must have been some dream," Henry said.

His worry showed clearly on his face, but Nikola gave him a sharp look. "Hey wolf-boy, kindly keep your opinions to yourself until I get a few more drinks in me."

Henry looked rather put out, and Nikola felt a twinge of regret. He'd been trying lately to be just a little nicer to him. He told himself it was for Helen's sake, but the fact was that he'd gotten fond of Henry, all on his own. Since moving to Hollow Earth, he had found that (occasionally) he even enjoyed working with him.

"You'll have to wait, I'm afraid," Helen said, still giving him a concerned look. "Are you sure you're up to the mission tonight?"

The mission. Nikola swallowed.

"Sure," he said, plastering on an unconvincing grin. "Vampire, remember? Hey, you know, isn't there some smuggling gang across town you need to bust? I can check this out myself."

"The big guy and Declan are on that," Helen said. "We're talking about multiple killings, Nikola, I'm not sending you off by yourself on this."

Nikola's jaw set. He knew that tone.

"Fine, fine," he said, raising his hands. "I'm just trying to be a helpful little Sanctuary employee. You know I could handle it."

"And who would watch out for you if I weren't there?" Helen asked, raising her eyebrows and favoring him with a warm look which he was sure was supposed to comfort him.

It did nothing of the sort, but Nikola managed a weak smile for her anyway. It had to have been a dream, right? In the back of his head, he knew it wasn't – it had been too vivid, and too similar to what was happening now – but whatever it was, he knew what was coming. If he had to, he could prevent it.

* * *

"This place is creepy as hell," Nikola muttered as they crept through the exact same hallway from before. All of it was there: the dust, the creaking doors, the noises getting closer and closer. Every nerve was on edge, his entire body twitching at the tiniest of sounds.

"Want to hold my hand?" Helen asked teasingly. He took the hand she offered in jest, lacing their fingers together and relishing her warmth again.

She gave him an odd look. "Nikola, you've been acting strange all night. Is there something I should know?"

"Helen," he said, and hesitated. She should at least be prepared, just in case. "The creature here… It may be a vampire."

"A vampire?" Helen stopped, turning to face him completely. "I hardly think that's likely. We destroyed the last remnants of vampire civilization. You're the only one left."

"Yeah sure, but what if that's not true?" Nikola looked around, stepping closer to Helen. "I mean, there might conceivably be some left somewhere, right?"

"Ah, no?" Helen said, her brow furrowed. "Considering you and I have both done extensive research on this, I highly doubt it. Unless there's something you're not telling me," she added, her voice taking on a rather dangerous tone.

"Well," he said. "I – recent events have brought to light the possibility that, uh, maybe the vampires I made in Rome aren't…completely…dead."

" _What?_ " Helen was furious. "You couldn't have mentioned this earlier? My God – several years ago, maybe?"

Her disappointment stung just as bitterly as it had before, and Nikola looked away, unable to meet her eyes. He didn't argue, because he couldn't: she was right. He could only hope that this time, his rank carelessness wouldn't get her killed. At least so far there wasn't anything to indicate the presence of vampires here, scenic similarities to his previous experience aside. Maybe it _was_ just a dream.

Nikola tilted his head. As if on cue, sensing his tentative hope, the sound he had been dreading this entire time issued from in front of them.

"Hold on one second," he said, and pulled her to the side, covering her with his body just as he had done before.

Helen jerked away from him as soon as the energy wave passed. "How did you know that was coming?" she asked, a disturbed note joining the anger in her voice. "Wait a minute. I know that weapon."

"Yeah, yeah, I built it. Don't bother trying Henry and Kate, they won't answer," he said as her hand went to her ear.

This proved the theory that had been taking shape in a corner of his mind, even though for once he hadn't wanted to be right. He and Helen both knew firsthand that time travel was possible; something like this was bound to happen eventually. But why was it happening _now?_

Somehow, time was repeating, forcing him to relive this day again. How many times would it repeat? Would he be thrown back again?

He couldn't bank on another chance to fix things – they needed to get out of here. But Helen was never going to leave Henry and Kate behind. He had clung to his ridiculous hope beyond the point he should have, and now, if anything happened to her here... Still, Nikola had the advantage of knowing what was going to happen. He could still prevent it.

Her eyes flashed. "You _knew_ they were in danger?"

"I hoped not," he said.

"Nikola," she said, her voice very low, "tell me what's going on. Right now."

"Well I'd love to, but we're going to be a little busy in, let me see, about five – "

His calculations were off, which he only realized when there was a snarling vampire crushing him to the ground.

"Nikola!" Helen shouted, firing into it.

"Go for its head!" he shouted back. Anticipating its movements, he managed to catch the vampire before it could get up and head for Helen. He pulled it back down to the floor with him, burying his claws as deep in its body as he could.

Whatever problems she had with him at the moment, Helen took his advice, and shot it several times in the head. It fell over – Nikola hadn't even had to shock it this time – and he loosed his hold on it. He jumped up and ran over to Helen, wrapping his arms around her and looking about wildly. Which direction had the other vampire come from again?

Helen disentangled herself from his arms. "Answers, Nikola. _Now_."

Nikola had just opened his mouth to answer her when a sudden jolt of pain coursed through him, followed by a wave of dizziness that made him stagger over to the wall and lean against it for support.

 _"_ _It'll be alright, Nikola."_

It was Helen's voice, but it wasn't coming from Helen where she stood in front of him. It seemed to issue from a long way behind him instead, and it was distorted somehow, as if she were underwater. While the Helen in front of him was still looking at him angrily, this Helen spoke reassuringly, and he could have sworn he had never heard her say that before.

Nikola twisted his head around, trying to catch anything else she said, but all he could hear were the echoes fading away into the shadows.

What the hell was that? Some kind of side effect of the time loop? Great. Like he needed to be any more creeped out. Although this could be a key to figuring out what was going on, if only he could concentrate on it. But concentration wasn't going to happen at the moment, when Helen was demanding answers and the second vampire was going to attack them any second. He turned back to Helen, shaking his head to clear it, and tried to focus on her.

"Nikola?" Helen was staring at him, beginning to sound worried again.

"Ok, short version," he said, taking her hand and holding on tightly. "We're in a time loop and you're about to be killed by another vampire." Helen's eyebrows went up as she opened her mouth, and Nikola hurried on before she could interrupt the important part.

"Watch that – yeah, that corridor. Actually no, wait, maybe you should stand over there – "

Helen's hand was ripped suddenly away from his as the other vampire came from behind him – he had been wrong about the direction, how had he been wrong? She gave a cry of pain, and Nikola whirled in horror.

The vampire was crouched next to her, and it was – Nikola shuddered, about to be sick. It was drinking her blood. In his efforts to prevent this from happening, he had only made everything worse.

He flung himself across the hall, dragging it away from Helen with a sharp hiss. The current he sent through them this time was even stronger than the ones he had managed before, and he fell to his knees once the other vampire was dead. Crawling over to Helen, he pulled her head into his lap.

"Helen?" Tears had already started to leak from his eyes.

"Henry and Kate," she began, and Nikola nodded.

"I'll take care of them," he promised, his voice shaking. "But you can make it this time, I know it, just hold on, Helen, please…" He wrapped her hand in his.

Helen's voice was barely a whisper, but the look she gave him was the same as before. "Nikola…"

A sob escaped him and he held her hand tighter, bending down to press his lips to hers. "I'm sorry, Helen." It came out brokenly, but he had to say it while she could still hear him.

"I'm sorry…I'm sorry…"

* * *

"Nikola?"

Nikola bolted upright. "Yes, my dearest?" His heart was pounding in his ears.

"Perhaps you'd care to go over the mission details again, for all of our benefit," Helen said.

He couldn't find any words this time; he could only throw himself across the room to hold her.


	3. Parallel Lines

"You're not feeling well?" Helen asked with a raised eyebrow, looking him up and down. "You didn't mention anything about it earlier."

"It just came on. Really, Helen, I feel awful," Nikola said. It was true…technically.

Nikola had been through the loop twice more – he was on number five now. The third time, he had told Helen about the time loop after the kids had left her office to start getting ready. He had been cautiously optimistic that she would believe him, and he had been right.

They'd been through so many weird things together that a time loop wasn't really _that_ crazy, and she trusted him. There might have been a time when Nikola doubted that, but after the years they'd spent together in the new Sanctuary, he was beginning to have a clearer idea of the depth of faith she had in him. Not that he always believed he deserved it, but the trust was there nonetheless.

But even though she had taken his word about the loop, she had wanted to go ahead with the mission anyway. She was determined to get to the bottom of these killings, and nothing was going to stop her. She had told him what he had believed at first: that they could alter the future now they knew it was coming. Since they were both forewarned this time, he had hoped that she was right.

They were both wrong.

The fourth time, he had told them all right there in Helen's office when the loop reset, Helen's hand firmly clasped in his because he couldn't quite seem to let go of her. He still couldn't talk Helen out of going, but they had all stayed together that time, hoping that a major change such as that might alter the course of events.

It had been even worse that time. Watching Henry break down beside Helen, the only mother he had ever really known, was something Nikola never wanted to so much as think about again, and instead of repetition dulling his own grief, it only became sharper instead.

After that, he just couldn't bring himself to try the same thing again. Since he couldn't talk Helen out of going by telling her about the loop, maybe he could convince her to stay by some other means.

So he had blurted out that he felt terribly ill, could she take a look at him? Maybe he wasn't really immune to the poisonous fangs of the hostile Hollow Earth abnormal that had bitten him two weeks ago. It had been the first thing that popped into his head to get Helen to at least put off leaving tonight, though he could think of many other better excuses in hindsight. This one, however, had the added benefit of being slightly closer to the truth.

But he wasn't above exaggeration. "My heart rate," he said. "It's really high, it won't slow down."

Helen sighed and put a hand on his neck, checking his pulse. "You're right," she said, frowning. "Is there anything else?"

"A little dizziness, and, uh, nausea. And fatigue."

Helen's eyebrows furrowed. "Hmm. Your vampirism should prevent anything serious…" She trailed off thoughtfully. "How much sleep have you been getting?"

"Uh." Nikola cleared his throat.

She gave him a disapproving look. "Perhaps you should stay home tonight. I'm sure we can manage without you."

"No, wait," he said, too quickly. "You can't go. I'm having hallucinations too."

The dizzy flash he'd had earlier had repeated a few times over the course of the last few loops, accompanied by more voices saying things he had never heard before, so he wasn't even really lying.

Nikola had formed a theory about what those were: some kind of temporal instabilities that were broadcasting the future back to him in unpredictable bursts. (He'd come up with a name, too, calling them temporal flashes. It was his best one since the ill-fated De-Vamper, in his opinion.)

It was total conjecture, but if time was already screwed up because of this loop, it was possible, and it made sense. Helen – it was usually Helen, though not always – said such random, mundane things that he couldn't believe it was anything other than a glimpse of events happening in a different time instead of some kind of communication.

Unfortunately, that also meant they were completely useless to him in figuring a way out of this thing. Unless he got really lucky, which Nikola doubted very much was going to happen at this point. Today didn't seem to be his lucky day.

Though as mundane as they were, they might be his only hope if he didn't come up with a better plan soon. From the looks of things, Helen wasn't going to fall for this act very much longer.

"Terrible hallucinations," he added desperately. "I think I saw a green nubbin crawling on Heinrich back there."

She looked at him for a moment before bursting into laughter. "Nikola," she said, her lips twitching. "Are you actually sick?"

"With love," he said before he could stop himself.

"Alright," she said in a businesslike way. "I doubt very much it's poison, but I'll run a few tests before I leave just in case. Even if I don't find anything, I want you to stay here and rest tonight – "

Nikola shook his head frantically. "No, no, I can't stay. I'm coming with you."

Helen sighed. Her face had gone through more expressions in the last five minutes than it had the time a baby dragon followed him home and he tried to convince her to let him keep it. "Nikola, ten seconds ago you were insisting you couldn't go anywhere. What aren't you telling me?"

"Would it be dreadfully maudlin of me to say 'I love you'?"

"Quite," Helen said, smiling a little. "Stay here, Nikola. Get some rest. We'll be fine. As a matter of fact, you've delayed us long enough for the big guy and Declan to get back, so Henry can stay and keep you company. How's that sound?"

She was using her "concerned doctor with a slightly muddled patient" voice, and Nikola rolled his eyes. He wasn't a _child_.

"Helen, I have to come with you," he tried one last time, catching her hand in his. He couldn't leave Helen to face his vampires, to face her own death, without him.

"Stay, Nikola. That's an order." Helen kissed him on the cheek before ruffling his hair. "You can work on the computer system while you're at it. I know you hate the file transferring, but it needs to be done."

"Aww come on, I've been doing that all day," Nikola complained half-heartedly.

"Well, there's a still a lot left," Helen told him. "But don't work on it too long. When I get back, I expect you to be in bed."

Despite everything, Nikola felt a faint smirk pull at his mouth.

"Getting a full night's sleep," she finished dryly before he could say anything. "Now get going."

Nikola sighed, getting up and heading out the door. He had at least delayed Helen – she was going to have to get Declan and Bigfoot ready to leave, which gave him maybe half an hour to come up with another plan.

He still didn't know how this time loop had started, but it led straight to Helen's death. No matter what it took, Nikola was going to stop it.

* * *

"Doc, get up to the lab, quick!" Henry's voice burst through the com system, jolting Helen out of her office chair.

"What is it, Henry?" she asked.

"It's Nikola – he's hurt."

Helen didn't need to hear anything else – she ran full tilt through the Sanctuary corridors until she reached Nikola's laboratory, bursting through the door to find him lying on the floor, Henry on his knees next to him.

"Nikola!" She dashed over to him. He was unconscious, his breathing shallow. "What happened?" she asked Henry.

"I don't know, we were working on the computers, there was some kind of electrical surge." Henry was babbling, sounding worried, and Helen couldn't blame him. "He got hit with some kind of discharge – I didn't see where it came from, it happened really fast."

Helen nodded, turning her attention back to Nikola, who was stirring next to her.

"Hi," she said, giving him an encouraging smile and patting his cheek. "Glad you're back with us. Don't think this gets you out of working on my computers."

Instead of responding to her teasing, he sat up with a rather wild look. "Where am I?" His voice rasped, as if he'd recently been ill.

Helen exchanged a confused glance with Henry. "You're in the lab," she told Nikola. "You're going to be fine." She motioned at Henry, who hooked one of Nikola's arms around his shoulders, Helen taking the other, and together they helped him to his feet.

"The infirmary," she said to Henry, then turned to Nikola, adjusting her arm so that she could rest her hand on his, lying limply on her shoulder.

"It'll be alright, Nikola," she said softly. "I'll take care of you."

Nikola only stared at her, his eyes wide.

* * *

Helen knocked on the door of Henry's lab. He had moved back down to his after the incident with Nikola, since the computers there now seemed to be well and truly fried.

Nikola had been acting very oddly tonight. After the accident in the lab, he had seemed half-unconscious, barely even making eye contact with her. When she told him he didn't appear to have suffered any lasting physical effects and he would be fine as long as he followed her orders and rested, he had given her an unreadable look and left the room with hardly another word.

She was worried about him – for one thing, Nikola had taken much worse of shocks before, and they hadn't affected him like this. And there was something else wrong with him too, underneath the surface. It had something to do with his behavior tonight, but Helen couldn't quite figure out what it was.

Whatever it was, it was unfortunately going to have to wait. The mission tonight was urgent; she had to check out the reports she'd received from the surface before anyone else got hurt. In the meantime, she could only hope that rest would help Nikola. Perhaps she could spend a little extra time with him tomorrow. It had been a while since they had worked together in his laboratory. Helen smiled. They would both enjoy that.

"Hey, what is it?" Henry asked, looking up from his computer.

"It's Nikola," Helen said. "I need you to look after him while I'm gone. I'm sorry to take you away from Erika." She was on the surface at the moment, but Helen knew Henry talked with her online whenever he could. "But I don't like to leave him alone when he's like this, and the mission – "

"No, I totally understand," Henry said. "I'll check in on him. Maybe get him to play a few rounds of Super Smash Brothers."

"If you think that'll help," Helen said, chuckling.

"I'll let him win, and I won't even make any Pikachu jokes," Henry promised. "It'll cheer him right up."

"Thank you, Henry. I really appreciate you doing this."

"Nah, it's no problem. He can be kinda fun to hang out with, if you give him enough wine and get him in a decent mood."

"Well, you have my permission to give him as much wine as you deem necessary," Helen told him, her smile faltering slightly. She'd empty the cellar if it meant getting Nikola back to normal.

Henry grinned. "Then I'll bring some up to him when you leave."

* * *

After he left Helen, Nikola rambled through the halls of the Sanctuary, trying to come up with another plan. So far, he'd been (unsuccessfully) focusing his efforts on making sure Helen stayed home tonight, but would that really be enough to break the loop? Or was it triggered by specific events instead? The exact timing of events had been different in each of the loops, given Nikola's various attempts to delay or avoid what happened, and yet they only reset when Helen died. Did she have to stay away from the warehouse district for longer than just one night? Hungry vampires weren't exactly bound by the time of day, after all.

Maybe he should concentrate on figuring out a way to get rid of them, or where they had even come from to begin with. It still didn't make any sense that they were back. Nikola would have sworn he saw them all dead, but the exact details of the memory skittered away every time he tried to grasp them, and the proof they were alive had been right there in front of him.

He made it all the way down to the abnormal levels without even realizing how far he had come before he was struck with another temporal flash, hard enough to knock the breath out of him. This was the worst one so far, and he had to stagger against the wall, bracing himself against it and closing his eyes in the hope that it might relieve some of the splitting pain behind them.

 _"_ _I can help you,"_ Helen said in his head, her voice tight. _"I_ will _help you, if that's what you need."_ For a brief second, he almost thought he could see her, standing behind her desk and looking at him with a level of apprehension that Nikola had hoped never to see on her face again. The image sputtered out, taking the pain and dizziness with it.

Nikola groaned, sinking down the wall and resting his head in his hands. Each of these flashes left him feeling more exhausted than the last, and here was yet another useless scene that told him nothing about his current situation. The only new piece of information he had gleaned was that despite her words, her expression told him future Helen had stopped being reassuring and started being disappointed again, which was only depressing rather than useful. For that matter, she might not even be future Helen. Nothing that he'd seen or heard had even happened yet, which meant his theory was still just that, and he had exactly what he'd started with: nothing.

It was so damned _frustrating_. He was a genius, for God's sake. He should have had this entire sorry business figured out in a half-hour with extra time for a glass of wine left over, but all he was doing now was blundering around like an idiot, trying hopeless plan after hopeless plan.

And the most annoying part of it all was that Nikola had a feeling that he already knew the solution and had just forgotten it. He had done quite a bit of research on time travel after Helen's experience – he had to have the knowledge he needed kicking around somewhere, but it just wouldn't come to him.

Nikola sighed and got to his feet, about to go back and try one more time to convince Helen to stay with him tonight, when another flash hit, a massive wave of pain burning through him. Involuntarily, he cried out, his legs giving way and sending him crashing to the floor again.

He heard Helen shout something, sounding furious now, but the exact words slipped past him, lost in the haze of pain. A heavy numbness pressed suddenly down on him, turning his limbs to lead, and he closed his eyes, trying to focus on Helen.

He could see her so clearly now, her eyes lit up with anger. She was almost certainly angry at him, but he couldn't help but spare a moment to appreciate just how beautiful she looked at that moment – well alright, all the time, but there was a particular radiance to her righteous anger that Nikola had always loved.

This vision was so much more vivid than the others had been, and it didn't seem to be fading away as quickly either. Nikola almost felt like he could reach out and touch her, if he could only get his body to respond to him.

Then it was gone as suddenly as it had come on, and a string of profanity in every language Nikola knew ran through his head, ready to be unleashed as soon as his voice started working again. He knew he had been getting somewhere – if it had only lasted for one more minute…

Like he'd willed it somehow, Helen appeared in his mind again, except now she was staggering up from the floor, a sizable dent in the wall behind her, blood trickling from her mouth. Nikola heard a low hissing growl, and his eyes snapped open in horror. That had been a vampire, and it had been in Helen's office.

So even if he got her to stay away from the warehouse district, she wouldn't be safe. If time was going to start course-correcting to Helen's death no matter what he did, Nikola had even less chance of finding a way out of this than he had before. Despite his reservations, leveling with her seemed the only alternative at this point. For Helen to dodge this, she had to know it was coming.

Some of the feeling in his limbs had returned, and he pushed himself up, keeping a hand on the wall to steady himself as he made his way through the hall.

He would tell her whatever he needed to in order to get her to stay – he would beg her on bended knee if he had to – and at least that might buy them enough time to work on a solution. She had been about to leave a short while ago, and that last vision had immobilized him for longer than he would have liked; if he was going to have the slightest hope of catching her, he was going to have to run.

* * *

If Nikola had been with Helen, she was sure he would have made a comment about dark corridors in abandoned buildings. What _was_ it with them, anyway?

Helen shook her head. She couldn't afford to start thinking about Nikola right now, because thinking about Nikola would lead to worrying about Nikola, and that was a distraction that seemed like a bad idea when one was creeping towards a potentially lethal creature. She glanced over at Declan, who nodded back.

There was a heavy scuffling noise from ahead of Helen, and she raised her stunner. The creature they were looking for appeared abruptly from the dark hallway stretching in front of her, moving fast. Helen barely ducked away in time, firing off a shot that missed by a mile.

"Bloody hell!" Helen swung around, the beam of light attached to her stunner finding it and blinding it for a few seconds.

It was the opportunity Helen needed, and she fired again, the creature dropping to the ground after a couple of blasts from the stunner. She and Declan walked over to it.

"Nice shot," he said.

"Thanks," Helen said. "Wouldn't have wanted be on the wrong end of those quills, trust me."

Declan winced at the thought.

"Kate?" she called.

"Yeah?"

"Be careful. We're definitely dealing with a jessaped nest."

* * *

Helen hadn't been in her office, or in the labs, or anywhere else she frequented in the Sanctuary. Nikola only had one more place to check before he gave in and admitted she had left before he could reach her. He could probably catch up to them on foot, though, which he was going to try if she wasn't here.

Out of breath and desperate, Nikola skidded to a halt in front of his and Helen's room and twisted the knob, throwing the door open and tumbling inside.

He looked around, and his breath drew in sharply.

Helen was standing in front of him, just finishing up strapping on her guns in that incredibly hot way of hers.

"Nikola?" she said, looking troubled.

"Helen," Nikola sighed, and he crossed the room in an instant, pulling her into his arms. He'd made it in time. Now they might have an opportunity to figure something out. "You're here."


	4. New Light

When Nikola woke up, he reached out for Helen before his eyes even opened. They had stayed up late into the night, discussing possible solutions, until Nikola felt himself start to drift off. As anxious as he'd been about Helen last night, he was surprised he had even managed to fall asleep at all; he must have been more exhausted than he'd thought. Besides, Helen had assured him that they would figure something out, and Nikola had let himself be comforted by her presence.

Instead of the reassuring warmth of her body curled up next to him, all he found was an empty bed. His fingers touched something cold as his eyes flew open, and he sat up, blinking at the tablet that Helen must have left behind her.

He turned it on to find a message from her:

 _Nikola,_

 _There was another killing in the warehouse district last night. I'm going to check it out, along with Henry and Kate. I suspect your time loop is broken by now. In any case, I've taken some of the advanced Praxian weaponry out of storage. I will use the utmost caution, but I'm sure you understand that I can't stand by any longer._

 _You seemed to need the rest, so I didn't wake you. Don't worry, Nikola. With your warning, I'm certain whatever potential future you saw can be averted._

 _I'll be back as soon as I can. Fix my house._

 _Helen_

"No," Nikola whispered, his stomach dropping out from under him.

Course-correction. He should have known Helen wouldn't be able to sit by for long if her idleness led to more deaths. After all his persuasion, she still must have thought she could change things.

Nikola bolted out of bed, but he knew before he even started moving that he was going to be too late.

How many more times was he going to have to live through this?

Before he could get far, his head exploded with pain as one of the temporal flashes hit. When he saw Helen this time, she was choking, her fingers scrabbling around the clawed hand gripping her neck. Nikola was already going to have to see this as soon as he made it to the warehouse district; he couldn't watch it again. But he couldn't seem to stop it.

The scene played out in front of Nikola like he was watching it on stage. She was dangling in the air in one of the top floor corridors of the new Sanctuary. One of the windows lining the halls had shattered, probably from the fight Helen would have put up, but the others were intact: he could even see a faint reflection of her in them.

Gasping for breath, Nikola finally managed to wrench his eyes open, the image of Helen dying in front of him mercifully fading away. His heart had been pounding, his mind filled with nothing but the all-consuming need to get away from that sight; freed from it, he was able to process what he'd seen this time.

More importantly, what he hadn't seen. Nikola went rigid with horror as he realized it. He would have screamed if he could, but he was still paralyzed from the effects of the last flash.

A light flicked on inside his head as the wall that had been frustrating him so much crumbled into dust. Nikola knew now why he was stuck in this loop, why his vampires had come back, and what the flashes were. He finally knew everything – even why it had taken him so damned long to figure it all out.

It was just such a shame he couldn't enjoy his newfound clarity, because it meant he would never be able to save Helen.

* * *

"Jessaped nest, huh?" Henry asked. "Ouch."

"Indeed," Helen said. "Still, it went quite smoothly, all things considered. How's Nikola?" She didn't beat around the bush; it was Henry, and he would know how worried she was.

Henry's face scrunched up in a look that did nothing for Helen's optimism. "I don't know," he said. "He wouldn't let me in. He was acting really weird. I mean, it's not like he's ever really _nice_ , you know, but he was a lot less nice than he usually is. If that makes sense."

"I understand perfectly."

"And he didn't even care about the wine I brought him," Henry continued, sounding even more disturbed. Helen frowned.

It might have seemed laughable that both of them took that as a sign that something was really wrong with him, but as unpredictable as he was, there were still constants in even Nikola's mercurial character.

His love for Helen was one – that certainty was always hovering at the back of her mind with a kind of comfortable hum – and science, discovery, knowledge, those things were another. Further down the list, but on it nonetheless, was wine.

"I'll go see him," she said. Whatever was wrong with him, Helen was going to find out tonight.

* * *

Nikola was in her office behind her desk when she walked in, reading one of her books. He snapped it shut when he heard her and turned around, smiling at her.

"Helen," he greeted. "You wanted to see me?"

"I did," Helen said, coming around the desk and putting her hands on his shoulders, giving him a tiny push so she could pull out her chair.

He didn't budge.

Her jaw tightened and she backed away, standing face to face with him instead.

"How are you feeling?" she asked, looking at him intently.

He broke their eye contact, strutting around her desk and still fiddling with the book in his hand.

"Much better, thanks to you," he said, tilting his head curiously. "What did you need?"

Helen kept looking at him for a moment in silence. "Tell me what's wrong," she said eventually. "Tell me, and I can help you. I _will_ help you, if that's what you need."

"I'm fine, Helen. Immortal vampire, remember?" He paused, the smile deepening and showing his dimples. "Not that you're not stunningly attractive when you worry about me."

"Don't," Helen said sharply. There was a gun under her desk and she had it out in a split second, pointing it straight at him. "Don't even try."

His forehead had creased. "Helen? What are you doing?"

"Exactly what it looks like I'm doing, unless you tell me one thing: what have you done with Nikola?"

He stared at her, blinking a few times. "Helen," he said slowly. "You're looking at him."

It was an echo of words Nikola had once spoken to her, meant to assure her of his sincerity, but it rang hollow.

Helen shook her head. "No, I'm not," she said. "Who are you, really?"

He looked at her for a long moment.

"Oh, Helen," he said at last, smiling again. "Don't tell me you don't recognize me."

Helen looked again into his eyes, Nikola's eyes, clear and blue, but cold and hungry; she had never seen Nikola quite like that. She felt a shudder run through her.

She did recognize him now, and without hesitation she fired three shots into his chest, leaping around the desk before he could recover and slamming her arm into his throat, backing him up against the wall.

"Hello, Helen." His voice curled around her name, the grin that wasn't quite Nikola's still fixed on his face.

Helen's own voice was cold in reply.

"Adam."


	5. Old Friends

**A/N: An update! I'm sorry about the wait. Between travel and work, life has been a bit crazy. The next chapter of this is about ready to go. After that, updates may be a bit fewer and farther between, but I'll do my best.**

 **Anyway, thank you for reading, and enjoy! :D**

* * *

"Give Nikola back this instant," Helen snarled.

Adam laughed. "What are you gonna do, shoot me?" His eyes went black, and he lashed out with a blow that sent her flying across her office.

Helen hit the wall hard and slid down, coughing. She picked herself up, her gun still grasped in her hand, and fired, hitting him squarely in the chest.

"Ouch," he said, glancing down. He grinned, suddenly looking and sounding so much like Nikola that Helen shivered. He had to be doing that on purpose to throw her off, but there was something else about the way he was acting, something forced, that Helen couldn't quite put her finger on. "Skipping straight to the fun part, huh? Not going to let me tell you all about how I survived?"

Backing away from him, Helen angled to her left, trying to circle around so she had a clear run at the door.

She raised her eyebrows in a challenge. "How _did_ you survive?"

Adam opened his mouth and staggered back as Helen shot him a few more times.

"Changed my mind," Helen said, giving him a hollow smile. "I don't need to know."

"Aren't you acting a little blasé about shooting me?" He sounded offended, peering with apparent fascination at his fast-healing wounds.

If she had needed any more proof he wasn't Nikola, that would have been it. "Not really," she said, and poured the rest of the clip into him.

Blood was starting to stain the front of his waistcoat, his abilities not catching up to the task of healing multiple wounds as quickly as one.

He was stunned long enough for Helen to dart past him, making it through the door. Her heart was racing, but her hands were steady as she reloaded her gun. She couldn't beat him with bullets alone, not with his abilities. She would have to think of something else, but until then all she could do was stall.

Adam's hand closed around her arm, jerking her to a halt, and she turned, shooting him again to loosen his grip on her arm before sliding around him and running down the hall. He caught up to her in another second, holding on much tighter this time and swinging her around to face him.

"This whole instant healing thing is amazing," he whispered. "I can see why Nikola enjoys this so much."

"Where is he?" Helen struggled against his grip on her, but she couldn't beat a vampire's strength.

"Safe and sound," Adam said breezily.

Helen didn't trust him for a second. " _Where?_ "

"Aww, Helen." There was that demented grin again. "Where would the fun be in telling you that?"

"Bastard," she hissed, and managed to twist her gun hand around and fire a few more shots into him before he knocked it out of her hand. It flew to the side, hitting a window and shattering the glass, and fell out of her sight.

Adam had his hand around her throat before she could make another move, his claws digging into her skin and drawing blood.

"You killed my daughter," he growled. For the first time, Helen caught a glimpse of the real Adam, flickering through his distorted Nikola impression. "And me. Three times. Four times. Your turn." He snarled.

Helen couldn't breathe – her throat was being crushed under his fingers, his claws cutting deeper. Her vision was starting to dim from the lack of oxygen, her struggling growing weaker by the second.

Somehow, it jarred Helen's memory of the last time she had experienced this: in the virtual chapel.

 _Ashley_.

Her gun was gone. She had no other weapons, and with her diminishing oxygen supply, her chances of taking a vampire out unarmed were low. She could barely feel her legs and arms now – she knew she didn't have much time left. No one else was here. Helen was alone, as she had always known she would be when death finally caught her.

She couldn't allow herself to give in. She was still needed here at the Sanctuary, and by the people in it: the abnormals, her residents, her team – the "children," as Nikola dubbed them – Nikola himself, lost or imprisoned somehow by Adam. But her eyes were closing in spite of herself.

The grip on her throat loosened suddenly and Helen's eyes snapped open as she went tumbling to the floor, coughing so hard she could barely gulp in deep, desperate breaths. She looked up, her head spinning, and was met by a sight she would have known anywhere: Nikola, staring straight back at her.

"Helen," he whispered.

"Nikola," Helen gasped with a momentary surge of relief. Adam hadn't been lying – he was still alive, for now. She staggered to her feet, still coughing. Nikola was standing stock-still next to her, his hands clenched, eyes unfocused.

"Nikola," Helen repeated, grabbing his arm. "You've got to fight him, alright?"

"Yeah, working on that," Nikola managed to snap through gritted teeth. "It's not really a walk in the – " His eyes closed suddenly and he twisted away from her with a cry.

"Nikola!" Helen seized his hand. "Hold on. Concentrate on me."

Nikola gripped her hand, breathing hard. His eyes opened, but they were glazed over, turning darker and redder by the second. He seemed to be lost in his own world. "I'm sorry, Helen…" he mumbled.

"Don't talk," Helen ordered. "Just concentrate. Come on, Nikola."

"I can't – " He shuddered again and dropped her hand. "Helen – go, get out of here."

"No," she said flatly.

"You have to go," Nikola insisted, strained. "I'm giving you a head start, now use it."

"I will not –"

" _Please_ , Helen, please just go." He nearly choked it out.

Helen backed off, staring at him, helpless to do anything for him in this fight. If she stayed and he lost, there'd be no helping either of them. And it looked like he was losing, his hands trembling at his sides now. Adam was about to make a reappearance, Helen was sure of it. How could she hope to stop him when he had Nikola's abilities?

Nikola's abilities. That was it, of course. How many times had he pestered her about them at Oxford, or in the last year, showing them off to her?

Just like that, Helen's plan was formed.

"I'm sorry, Nikola," she whispered. She darted away down the hall, leaving him standing rigid in the center of the corridor.

Helen fumbled for her cell phone while she ran, dialing Henry.

"Hey doc," he said, sounding confused. "Why aren't you using – "

"Adam," Helen said into the phone breathlessly. "It was Adam, not Nikola – "

" _What?_ "

"You need to listen, Henry," Helen told him, daring a glance over her shoulder. The hallway was empty behind her. Nikola was still been buying her as much time as possible. "Lock down the Sanctuary, right now. And then get down to the abnormal levels. I have a plan but I need you to get it set up, and quickly. I'll try to distract him until you're ready."

"What do you need?"

* * *

Helen dashed into one of the larger rooms on the abnormal levels, whipping the door closed and leaning against it with a heavy intake of breath. She closed her eyes briefly and then looked around.

Henry rushed towards her, Will following close behind. Sally, floating in her tank in a far corner of the room, swam to the edge of the glass and pressed her hand against it, her concern a low murmur in Helen's mind.

"Doc!" Henry exclaimed. "You ok?"

"Fine," Helen said, still taking deep breaths. "For the moment. Is everything ready?"

"Yeah, it's good to go. Is Nikola ok?"

"No," Helen replied, her body tensing. "He's not." She swallowed, pushing her worry down for the moment. There would be time to deal with that later.

"What's – did I hear something about Adam?" Will asked, looking as disturbed as Helen felt.

She nodded. "I don't know how, but…" A noise sounded from the hall outside, and she sprang away from the door, pushing Henry and Will in front of her. Will slipped in the deep coating of water on the floor, and Helen pulled him up by his arm, getting them all to the other side of the room near Sally's tank, where the floor had been completely dried.

"Ready, Henry?" she asked.

Henry gave her a nod.

"As soon as he comes in," Helen said. Truthfully, she was only hoping this would work – she'd never done it before. She'd never had to.

The door swung open, crashing against the wall, and Adam strode in. His eyes connected with hers, but before he could do anything Henry had set off their trap.

Adam screamed in pain, and Helen watched as a massive amount of electricity crackled through him, lighting up the room in blinding flashes. It wasn't enough to kill him – they didn't have near the resources for that – but Henry had done his work well, and it would have been enough to stop even Nikola in his tracks for a minute. Helen was banking on the fact that Adam wouldn't have the same resilience that Nikola did.

It was true that some of his electrical powers were innate, simply going along with his vampirism. But Nikola had spent decades fine-tuning his control over his abilities, building up his resistance: she didn't think Adam would be able to match it his first time using them.

And it looked like she had been right. Adam had staggered and fallen to one knee, still shrieking – he was getting overwhelmed by the current, and the less he was able to concentrate, the more it would overpower his defenses. Another few seconds later, he collapsed entirely, convulsing.

Henry was about to shut it off, but Helen laid her hand over his to stop him.

"Another few seconds," she said, her voice thick. She needed to make sure Adam wasn't pulling some kind of trick, even if every molecule in her body was shouting at her to stop. That was Nikola in there too.

Henry looked at her with wide eyes before nodding. Helen counted to three before she couldn't take it any longer, and turned off the current herself.

The room went dark; they had blown the lights. Helen hadn't even noticed in the lightning storm. It took a moment before the backup power kicked in. Sally was clearly agitated, and Helen sent as reassuring of thoughts her way as she could manage. She wished they wouldn't have had to do this here, but it had been the only place close by that had contained everything they needed on short notice.

As soon as everything had settled and Helen thought it was safe, she ran over to Nikola, or Adam – they were both unconscious, so it didn't much matter. She knelt, making sure that he was still alive, as the big guy burst through the door.

"Just in time," she said, nodding at him and stepping aside so he could pick Nikola up as though he didn't weigh a thing. His arms and legs dangled in the air.

"Will, stay here with Sally. Henry, come with me. Hurry," she told Bigfoot. "We don't have much time before he wakes up."


	6. Going In

They put him in one of the cells, strapping him down with the same titanium webbing they had once used on the young vampires Nikola had created. Helen stayed with him while he was unconscious, checking him over to make sure they hadn't caused any lasting damage.

If she let her hands linger on him gently, or brushed them through his hair, no one else mentioned anything about it. Despite her best efforts to quash it, Helen had held out a faint hope that they had gotten rid of Adam with the electricity – she felt her heart sink when his eyes opened and he immediately strained against the bonds, snarling at her. She left quickly after that. She knew only too well how dangerous Adam was once he started talking.

"Alright, gentlemen," she said, watching him through the cell wall. "I'm open to suggestions."

She looked back at her team, all watching her in silence.

"Don't all speak up at once," she joked weakly, and sighed. "Henry, do you think it's possible to separate Adam from Nikola's mind somehow?"

Henry looked almost as dazed as he had when she had given him an authentic lightsaber prop from the filming of Star Wars for Christmas.

"Oh, man…" He trailed off. "I'm sorry doc, I don't think so. We don't really have a way to tell them apart. Maybe if Nikola were here, we could use his abilities. But without him, I just…" He shrugged helplessly.

Helen nodded. She hadn't really been expecting a different answer. "I understand." She thought for a moment. "Nikola regained control earlier, for a short period. Maybe it's possible that if we give him enough time, he could do so again."

She knew even as she said it that it was an even longer shot, and she had to agree with the doubtful expression on Will's face.

"I don't know," he said. "It wasn't for very long, right? And it was only once. Whatever he's doing to suppress Tesla, it must be pretty effective."

"Well," she said, crossing her arms with a resigned exhale. "Then there's only one thing left to do."

"What's that?" Kate asked.

Helen looked back into the cell. "I'm going in."

"Wait, as in, go into his mind?" Henry asked.

"Precisely," Helen said.

"Oh man," he said again. "That _never_ works out! Adam will cross over into you and melt your brain or something."

"Just let me get one thing clear," Kate interrupted. "By 'never works out' you mean 'never works out on TV,' right?"

"Yeah, but that doesn't mean it won't happen now," Henry said somewhat defensively. "And it's gotta be a strain on him, having two people in there already. You add a third, it'll probably be _his_ brain getting melted."

That was a good point. "Alright," Helen said. "Then we'll upload us all into a neutral location – the computer. Isolate us, so our system isn't in jeopardy again. I'll take care of Adam, and you transfer us back to our bodies."

"Take care of Adam…how?" Will asked.

"I'll figure something out. Henry, start getting everything ready."

"Ok, doc," Henry said, still looking worried. "I'll call Erika. It'll go a lot faster with her help, plus she can monitor you while you're inside."

"Very good."

After a quick message to Erika, Henry tasked Bigfoot and Kate with carting the necessary equipment down and busied himself getting it set up, leaving Will to continue looking at Helen with concern.

"Magnus, can I talk to you for a second?" he asked.

"Of course, Will," Helen said. They went a little way aside from the others to talk in a corner.

"Look, I know you want to save Tesla," Will began. "But have you considered that maybe going into the computers again is exactly what Adam wants you to do? He had to know you'd figure out what was going on, and whatever he's planning, he could probably do it a lot more easily from the Internet than from a single body."

"Possibly," Helen admitted. "Though you didn't see how hard he was trying to escape from there last year. And I don't think he expected us to discover or defeat him so quickly. He was really trying to fool me earlier; this wasn't part of his plan. In which case we have the advantage right now, and we need to press it, before – " She stopped.

"Which brings me to my next question," Will said, speaking gently. "Have you thought about the possibility that Tesla…well, that he's…"

"That he's gone?" she asked bitterly. "That Adam destroyed whatever was left of his mind as soon as he could? That my first priority should be saving the world from an insane AI instead of one person?" Her voice was sharp. "Yes, Will, I have considered that."

Will didn't say anything, and Helen suddenly felt very tired. She sighed, closing her eyes for a moment.

"I know Adam," she told Will. "He could have set his plans for me and Hollow Earth into motion by simply grabbing me off the street, but instead he chose to trap me in a time dilation field and torment me for hours."

Will nodded. "He wants to make the people he thinks have hurt him suffer."

"As much as possible. I may be the primary object of his grudge, but I don't believe he ever held the other members of the Five completely blameless. And after our encounter with the Praxian nanite last year, he probably hates Nikola almost as much as he hates me."

"So you think he's keeping Tesla alive to torture him instead of killing him right off the bat?"

"I do." Helen's fist clenched, her nails digging into her skin painfully. Whatever he was doing to Nikola, Helen was going to put a stop to it.

Will blew out his breath, shaking his head with an overwhelmed look. "Wow. That's a pretty messed up thing to hope for."

"It's a pretty messed up situation," Helen said. "Do you see now why I have to do this? There's a real chance Nikola's alive in there, and I can't just write him off, Will. I won't."

Will still looked unconvinced – after all, she'd just told him Adam held more of a grudge against her than Nikola, and she was about to hand him a golden opportunity to do something about it.

"If it were Abby…" she said quietly. An unfair strategy, perhaps, but a necessary one.

Will sighed, conceding to her. "Well, just be careful, alright?"

"I plan to. In fact, Henry has just given me an excellent idea for a contingency plan."

"Now we're talking!" Henry called.

Helen smiled for the first time in what felt like weeks. "Henry, I believe it's time to put some of our new Praxian equipment to use."


	7. Manifold

Nikola hadn't lost count of how many loops he'd been through, but he was trying not to remember.

He was exhausted.

Somehow, even though he knew that the exact same amount of time passed in each loop, it seemed like he was getting less and less breathing room between waking up in Helen's office and being in the warehouse district with her.

It was impossible, but then when nothing was real, impossible started looking pretty damn normal. Nikola was certain he had Adam to thank for this. Little bastard. And he couldn't even rip his throat out, since it was Nikola's throat now too, and he was rather attached to it.

Even the consolation of knowing everything that happened to Helen here wasn't real was only temporary, if Nikola was any judge. There was a constant aching pressure in the back of his mind that was more than just a headache. He could feel it trying to creep over his memory of what was happening to him, to destroy his already thin connection to reality. Adam again, no doubt.

Nikola had kept him occupied as long as he could, earlier. He'd seen Helen make it safely away, but he had no idea what happened after that. The flashes he'd been having, which he realized now were of reality and not the future as he'd first thought, had all but disappeared once he'd been forced back here.

There had been only one since then, and Nikola hadn't been able to see or hear anything – that one had been nothing but intense, white-hot pain. He was hoping it had been some kind of plan on Helen's part to subdue Adam, but he was assuming since he was still in here that either it hadn't worked or it was only stage one of a larger scheme. (If it had been Adam messing with his body, there was going to be hell to pay.)

Whatever the case, Helen would win eventually. For Nikola, that wasn't speculation so much as certainty. She'd come get him; she always did. In the meantime, he could stop Adam from taking complete control.

And get through this damn time loop. One thing was for sure, Adam had managed to come up with a hell of a way to torment him. Even though he knew it was quite literally all in his head and there was no way to save Helen, he kept trying regardless. Part of it was his hope that with each new loop he might gain some piece of information that could help him find a way out of this thing. But mostly, Nikola just couldn't bear to leave her, any version of her, to die alone.

Of course, he'd kept failing too. Adam hadn't set up this scenario intending to let him succeed. He might have known now it wasn't real, but that didn't bring him a whole lot of comfort when Helen was dying in his arms.

Nikola sighed and downed the last bit of the bottle he'd worked his way through this loop. He checked the time. Pretty soon, Helen would come through the door asking him if he was ready to leave, and he would be off for another exciting trip through the warehouse district. Though if he hurried, he might be able to make it through at least half of another bottle. Instead, he sank deeper into bed, rolling over to Helen's side with another sigh.

Closing his eyes, Nikola inhaled as deeply as he could. Now that he'd gotten rid of the obscuring influence of Adam in his head, he could tell that the details in here were off. The wine, for example, was awful. Helen would never have betrayed him by stocking something so inferior. But the scent of her lingering here on her pillow, that was _perfect_. He kept his eyes shut, letting it comfort him a little.

The door to their room opened and Helen's boots sounded on the wooden floor.

"Hey, Helen," he said, voice muffled in her pillows. He rolled over to find her looking at him with a strange expression.

"I suppose you want to go check out those killings in the warehouse district now?" he asked dully.

"Nikola," she breathed. She crossed the distance between them in a few strides and wrapped her arms around him so tightly he could hardly breathe.

"Ow. Wasn't expecting that," he wheezed, but not before seizing the opportunity to lean into her, his arm snaking around her waist.

"Are you alright?" she asked, pulling back and resting a hand on his cheek, stroking it absently while she peered at him.

Nikola blinked, staring at her. A tiny hope flickered somewhere in his chest – surely, it couldn't be…

"I'm fine. Helen, are you – "

"Yes, it's really me," she said. "Be honest, Nikola."

He stayed frozen to the spot, still looking at her with numb disbelief. He wanted to believe her, so very badly; he'd known she would come, but… it was so hard to tell what was real anymore.

Helen was watching him closely, concerned. She reached down to take his hand, pressing it between hers.

"Nikola," she said. "I had Henry upload us all back into the computer, but you should still have your electromagnetism. Use it. You should be able to tell the difference between my brain and a computer program, I hope," she added with a wry smile.

Nikola passed up the multitude of comments he would usually make at that and looked down, concentrating on Helen's hand in his. She was right. They _were_ back in the computer – he could feel a change in the environment now that he was looking for it.

Their entwined hands faded out of focus as Nikola poked around a little more. Beyond the smoothly running background computer operations, he could feel an infinitely more complex stream of data, that he had only seen once before.

He looked back up at Helen. "You know, I was kinda hoping you were going to go the 'tell me something only the two of us know' route. Like how much you lo-"

Helen silenced him in the most efficient way possible: by pressing her lips to his.

The kiss didn't last very long – not as long as Nikola would have liked – but when they separated, he felt a small smile struggle to the surface. It was probably a little pathetic, but it was the first one he'd managed for some time.

"You're here," he said softly.

Helen studied his face, moving one hand back up to cradle his cheek. He hadn't thought it possible, but her grip on him got even tighter.

"Tell me everything." Her voice was calm, but there was an undercurrent running through it that told Nikola someone was going to get shot before the day was out, and for once it wasn't going to be him.

* * *

"A time loop," Helen repeated after he had relayed the whole story. She was sitting next to him, one arm clasped firmly around his shoulders.

"A crappy time loop, but sure." Nikola closed his eyes, resting his cheek against her hand.

"Why do you say that?" she asked.

He shrugged. "Details are different every time. Anything that would save you changes from one loop to the next. Timing of events, or – or where the second vampire comes from, that kind of thing. Adam obviously wasn't too concerned with winning time loop of the year when he created it."

She chuckled and Nikola took a moment to savor it, turning his head to kiss her fingers. "The point is," he said, opening his eyes and sitting up, "you die, every time, and there's nothing I can do to stop it because he's made the damn thing impossible to beat."

Helen's free hand drummed against her leg. "Perhaps," she said. "Or perhaps you just haven't been looking at it the right way."

"Oh, and what way would you suggest I look at it?" Nikola asked, rather offended.

"You've been concentrating entirely on preventing my death," Helen said, completely unruffled by both the subject matter and Nikola's now dented pride. "What if that's not what's resetting events?"

"It is," he said, his exhaustion creeping into his voice. "Just trust me on this."

Helen shot him a worried look, but let the matter drop. "Well, there has to be a way to break the loop somehow."

"Does there?" he asked bitterly. "It's not like Adam feels an overabundance of generosity towards us. And even if we do, what happens then?"

"One step at a time," she said. "Think about this. Adam has access to your mind. What's worse: a puzzle that has no solution, or one with a solution that's continuously being pulled just out of your reach?"

She watched his expression changing for a moment. "Exactly," she said. "He knows it'll be harder on you if there really is a way to break it and he's preventing you from doing so."

"You have an evil mind," Nikola said with admiration.

"I try. Besides, we're in the computer now. Even if we're still in the program he constructed for you, he no longer has control over the outcome." She paused. "Hopefully."

"I feel so inspired."

Despite his sarcastic tone, Helen's mere presence was sending warmth curling through Nikola. It was only a dull, tired sort of contentment at the moment, but she had given him hope, for the first time in a while. He closed his eyes again and leaned against her.

Before he could get too relaxed, there was a rattling at the doorknob. Helen let go of him immediately and had a gun out covering the door faster than he could start complaining at the lack of contact.

The door opened, and Helen walked in.

"Oh," said the Helen next to him, lowering her gun. She cleared her throat. "Hello."

"I had a dream like this once," Nikola said. Helen elbowed him in the ribs.

The other Helen stared at the two of them for a full five seconds before speaking. "Bloody hell."

* * *

As he watched his Helen and virtual Helen deep in conversation about the situation, Nikola had a surreal sense that he should be enjoying this more than he was.

"Fascinating," they said in unison, peering at the other.

"A perfect simulation," Helen added.

"So you say," said the other Helen. "But how do I know I can trust you?"

"Nikola's word isn't good enough for you?"

They both snorted.

"Hey!" Nikola protested.

"Sorry, Nikola," they both said, unapologetically. Helen – his Helen – gave him a reassuring hand squeeze before rising.

"Let's go to my office," she told the other Helen. "There's something I need to get. We can have a talk on the way."

* * *

Whatever they talked about, virtual Helen was completely convinced by the time they came back. Nikola had a few guesses, but he knew he would never find out if he was right. She led the way to where Henry and Kate were waiting, while Helen and Nikola trailed behind.

Nikola looked over at the slender box that Helen was carrying. "What's that?" he asked, nodding at it.

She gave him a long look before opening it. Inside lay a silvery cylindrical object that Nikola was a little too familiar with.

"The De-Vamper," he said, surprised. "I wondered if you'd brought that to Hollow Earth with you."

"Actually, I didn't. But since this whole simulation is built on your memories, I suspected I might find it where you thought it was," Helen said.

Nikola glanced at her, his curiosity piqued. "So where is it, really?"

Helen looked away, waiting just a little too long before responding. "I destroyed it. In any case, this should be quite effective against your vampires."

She was right, but that wasn't the most interesting part of what she'd just said. "Why?" he asked.

"With the regularity that my Sanctuary gets broken into?" she said, giving him a look. "I didn't want to take any chances. Now, can you charge this for me?"

Her brisk tone left no doubt that she wanted to change the subject, but Nikola had heard enough – she had wanted to keep him immortal. She'd protected him, and he hadn't even known about it until now. He nodded, smiling slightly. "I might not be _quite_ as electro as I once was, but I can give you a few ex-vampires."

* * *

"You know, Nikola, I always thought you had more of an imagination than this," Helen said, sweeping her flashlight across dark corridors that were by now very familiar to Nikola.

"Hey, Adam was the one who dreamed this up, not me," he said.

The other Helen turned around. "Excuses, Nikola."

He raised his eyebrows with a wounded look. This was just _weird_.

She turned back, and Nikola found himself still staring at her back, his mind wandering into less pleasant territory. Helen was too confident about breaking this loop, he was sure of it. He was going to have to watch it all happen again very soon.

"Nikola," Helen said from beside him, and took his hand, giving him an encouraging nod.

It probably would have been more comforting if it didn't give Nikola such a disturbing sense of déjà vu. He smiled weakly at her.

She squeezed his hand; she had always been able to tell when he was lying. "We'll find a way," she told him quietly.

"Optimist," Nikola accused.

"There's no need to be insulting, my dear."

A thrill ran through Nikola; it was _so_ unfair when she called him that.

"I'm simply stating a fact," she continued. "After all, there's something in this loop that ensures our success."

"Oh yeah, what's that?"

She smiled. "I'm here."

Nikola stopped, but before he could say anything, the distant rumbling he had gotten so used to emanated from up ahead. Virtual Helen turned back to Nikola.

"Do you hear that?" she asked.

"The Cabal's weapon," Helen said.

"Get over," Nikola warned the other Helen, grabbing the real version and pulling her with him over to the side of the wall.

He'd been through this so many times he hardly even noticed the blast of heat anymore, but he looked over to Helen, squinting through the wave of light and pressure. She'd gotten out of the way in time and was hanging onto the wall, her eyes shut.

When it was over, virtual Helen stepped out into the corridor, looking after the blast. "I know that weapon," she said.

"Yeah," Nikola said, resigned to playing out the usual script. "That's cause I – " He stopped. "I built it," he said. He looked back at the real Helen.

She raised her eyebrows at him. "Don't keep me in suspense."

He started pacing in circles around her. "The weapon. The energy wave it sends out reaches across this entire facility. The direction the vampires come from – wherever they are, it changes every time. But with that – "

"It doesn't matter," Helen finished.

"That thing packs a nasty punch," Nikola said. "I should know. If we can set if off in time, it should take them out long enough for us to get out of here." He glanced at the other Helen. "Safe and sound."

"Well done, Nikola," Helen said, beaming. "Can you find the weapon in time?"

Nikola held up his hand, letting a few sparks dance across his fingers. "Electromagnetic, remember? I can find it."

"Then go," Helen said. "I'll stay with her and fight off the first vampire. Just get to that weapon before the second one shows up and – ah – "

"Right." Nikola took a few steps away, then hesitated, looking back at her. "Good luck, Helen." His eyes shifted to the other Helen. "Both of you," he added.

She nodded. "You too."

Then he took off and didn't look back.

* * *

"Go for its head!" Helen shouted. Her grip on the vampire's wrists was slipping, its claws inching closer to her face.

She was rewarded with the crack of her own gun firing from a few meters away. The vampire flinched back, its hands going slack. It recovered quickly, hissing, but not before she had drawn the De-Vamper from her jacket and plunged it deep into the vampire's chest.

Its light was enough to illuminate the dark hallway, reflecting back from the vampire's black eyes. Helen pushed it over and rolled on top of it, driving the De-Vamper even further in. The eyes turned gradually from black to brown, and Helen could see the shock and disorientation in them that she had once seen in Nikola's. Another blow from Helen was enough to incapacitate it.

She got to her feet, breathing rather heavily. "Good shooting," she said.

The other Helen nodded, grinning, and Helen found herself grinning back. She retrieved her gun from where she had dropped it and reloaded.

It was up to Nikola now, but that didn't mean she couldn't be prepared.

* * *

Nikola could feel the power the weapon was drawing to itself pulsing gently in a corner of his head, pulling him towards it. Sometimes it faded into the background, lost underneath the other, stronger pressure on his mind, but he could tell he was almost there.

The guttural hiss coming from behind him was the only warning he had that he was no longer alone. Nikola dared a glance behind him to see another vampire hot on his trail. So all three of his former creations were present. This one must be a guard, left behind to make sure nobody messed with the weapon.

"Guess that means I'm close," Nikola muttered, glad that his enhanced strength and speed allowed for witty remarks while running for his life. Still, he increased his pace, even at the cost of lost breath. He didn't feel like making witty remarks anyway – that last one had been kind of pathetic.

He rounded a corner and suddenly the weapon was on him – or he was on it, rather; he almost tripped over it, stumbling and losing his momentum. The other vampire had nearly caught up to him and he dived for the weapon's control, lying on top of its boxy shell. He managed to snatch it just as claws dug into his back, dragging him away from the weapon as teeth sank into his neck.

Nikola should have been used to it by now, as many times as he'd had to deal with these damned things, but the pain still made him give a cry. He kept his hands tight on the control though, fingers flying in an old remembered sequence. He was on the wrong side of the weapon, but Helen's time was running out – for all he knew, it might already be too late. It had taken him longer to find the weapon than he'd anticipated. He couldn't afford to wait.

The second after he pressed the final button, there was a roaring like thunder in Nikola's ears and he was flung off his feet, the energy wave throwing him far down the corridor and into a wall. Its force was enough to keep him suspended in mid-air for a moment, then the wave passed down another hall, back the way he'd come, and Nikola tumbled to the floor.

He stayed there for a moment, too exhausted to move, as he let his regenerative powers take care of the worst damage. Then he tilted his head, wincing as he felt a few bones snap back into place. Hearing a similar noise from off to the side, he glanced over. The other vampire had been caught by the wave too, and it was picking itself up.

 _Helen,_ Nikola thought. Had he set the weapon off in time? Surely even if he hadn't, the combined force of two Helen Magnuses would have been enough to stop anything they faced.

Snarling, the other vampire staggered up and towards him.

"Oh, come on," Nikola groaned. "I made you guys way too dedicated to your job." Bracing himself against the wall, he managed to get to his feet.

"Ok then," he said, his eyes turning black. "You know what? I'm tired. I've been locked inside my own head, had my body stolen by a psycho computer program – " and been forced to watch his adored Helen die more times than he cared to count – "and you wanna know what the worst part is?" He hissed. "The wine doesn't even taste right. So if you – "

His words were cut off by two gunshots firing simultaneously. The other vampire went limp and collapsed. Nikola's eyes were drawn to the source of the sound.

Helen stood in the center of the hall, breathing hard. Blood dripped through the fingers of the hand she had pressed to her neck, the other one steady on her gun. Next to her with her own gun raised stood her virtual doppelganger, very much unharmed.

"Helen," he whispered. She'd done it – they'd all done it. They'd broken the loop.

The force pressing against his mind disappeared like it had never been there. He hadn't even realized how strong it had been until it was gone; the relief left him feeling dizzy.

"Nikola, are you alright?" Helen asked, hurrying forward.

He fell back against the wall. "Just peachy." He closed his eyes, opening them again when Helen reached him.

"You're alright," he said softly. "You both are."

Helen smiled. "Of course." She stretched her hand out to him, and he took it and pulled her against him. Just for a second, he buried his face in her neck and breathed her in.

For those few moments, everything seemed quiet and still; for the first time in what felt like weeks, Nikola felt his racing heart finally start to slow. He took a shuddering relieved breath, ending in a kind of strangled sob that he muffled in Helen's shoulder. Tears pricked at his eyes behind his closed lids when her arms came up to encircle him. Adam was still a lingering threat on the horizon, but this, this long nightmare, was finally over.

And then, too suddenly for Nikola to react, the world seemed to shatter like glass. Helen, the other vampire, and even the hallway went spinning away from him as he fell backwards into nothing.


	8. Overload

Nikola opened his eyes and saw nothing but a swirling, confused mass of grey at first. He could hear Helen speaking, and though her voice seemed to be coming from a long way away, it got louder and clearer the more he focused on it.

"Nikola?" she said, abruptly right next to him, and everything snapped into focus. He and Helen were standing in the Old City Sanctuary laboratory, and her hand was resting on his arm.

"Déjà vu," he said, looking around. Helen's hand dropped from his arm and he took it in his. "Need to learn some new tricks, Adam," he said, raising his voice. "You know, Helen, I'm disappointed – it's just the same old, same old with him."

Helen chuckled, squeezing his hand before her eyes focused on something past his shoulder and her face hardened. "Not entirely the same, I'm afraid," she said, nodding towards it.

Nikola looked over. "Well, that's creepy," he said.

He could only assume it was Adam standing there, since in every respect it looked like a mirror image of himself.

"It does seem to be the day for these things," Helen pointed out, resuming her grip on his arm.

"At least your doppelganger wasn't evil," he said.

Adam grinned at them. "Hey, Nikola. Thanks for the body."

"You're not welcome. I want it back," Nikola said petulantly. Helen sighed.

"Alright, Adam," she said. "I'm certain in the time it took us to beat your little game that you've discovered there's no way out of the system this time. We've locked you in."

He started pacing around, fiddling with his hands. "Yeah, I did figure that out. Good job on that, by the way. Nice trick with the, ah, the electricity. I did _not_ see that coming."

Helen's fingers tightened on Nikola's arm. "You can drop the charade now," she said, and he could hear her frustration leaking through. Adam wearing his face must have bothered her more than she was letting on. Nikola would have been touched if the whole thing weren't making his own skin crawl.

"You've got no one fooled anymore," she went on.

Nikola stared at him, taking a step forward. "I don't think he can."

"Henry and I scanned the computer for you," he said. "Just in case, after the nanite fiasco. But we didn't find you. How did you manage that?"

Adam shrugged. "Maybe I'm just that good."

"You deleted parts of your program," Nikola said, ignoring him. "So we couldn't detect you. The original personality went first, right? The most non-essential component…"

Adam didn't say anything.

"And then you built yourself back up with mine," Nikola continued. "To try and fool Helen, which obviously didn't work out too well for you."

"I should say not," Helen interjected.

"It never does," he said, giving her an innocent smile. "Trust me, I've taken the bullets to prove it."

A faint growl issued from Adam's throat, his smirk sliding off his face. Finally, Nikola was able to get under _his_ skin.

"So Helen, what's that put us up to?" Nikola asked, delighted at the furious look in Adam's eyes. "Five times now we've killed him?" He glanced at Helen in time to see her expression change, and she looked away.

Guilt stabbed at him; he shouldn't have said that. He'd gotten too wrapped up in gloating. No matter how big a bastard Adam was, Helen would always regret what she'd had to do to stop him. That was who she was.

Helen looked back at him and Nikola opened his mouth. He couldn't apologize in front of Adam, but he could say _something_. She would understand.

Then, like a switch had been flicked on somewhere, the pressure inside his head was back, no longer a distant ache but crushing, overwhelming – blinding white light covered Nikola's eyes and he fell to his knees, his mouth open in a silent scream.

Through the sudden ringing in his ears, he heard Helen call his name, then command Adam to stop. Impossibly, he obeyed; Nikola collapsed entirely as soon as he was released, gasping for air.

"My world, remember?" Adam said. "You can't beat me in here."

"You're right," Helen said, stepping between Nikola and Adam. "But you don't want to stay here forever. You want out."

"Right," he said. "And you're going to help me."

"And if I don't?"

"Oh, Helen," he said, voice quiet. "Do you really need to ask?"

Helen stiffened.

"First bodies, now you're stealing our lines," Nikola choked, levering himself upright and wishing he hadn't when his head nearly exploded with pain again. "Bastard."

"Nikola," Helen said, exasperated. "You're not helping." Still, she reached down and pulled him to his feet, letting him lean heavily on her. Her arm was so tight around him it was almost painful, but Nikola welcomed the reminder of her presence – his head was spinning so badly he wouldn't have put money on being able to remember his own name.

"What do you want, Adam?" she asked.

"Pretty straightforward, really," he said. "You let me out of here and let me take Nikola's body."

Helen considered him briefly. "And why would I do that?"

"Come on, Helen. I'm sure I can find a way to get out without you, but it'll be a lot easier if you're helping me. If you do, I'll let you keep him alive in here."

"Oh, that's real generous of you," Nikola put in.

Adam ignored him. "If not – " He snapped his fingers. "I'll delete every trace of him."

He was bluffing. He _had_ to be bluffing. There was no way even Adam had the capability of wiping out that much data. If he did, wouldn't he have done it last year?

Helen was silent for a minute. "I have an alternate proposal," she said at last.

"Yeah, go to hell," Nikola muttered.

He could see her lips twitching even through his still-fuzzy vision.

"Not exactly." She looked directly at Adam. "Take me instead."

* * *

 _"_ _No!"_

Nikola's broken cry echoed throughout the virtual lab. Helen had to steel herself before she looked over at him, regretting it immediately. His eyes were wide; he looked lost, and Helen almost changed her plan on the spot.

Almost.

"Why would I do that?" Adam asked. "I mean, I have all these cool superpowers now."

"You'll still be immortal," she said, tearing her gaze away from Nikola. "You'll have more power and resources than Nikola ever did. I control the entire Sanctuary network, remember?"

"You wouldn't after Nikola here tells everyone you've had a little personality change."

"Wake yourself up before him then – I'm sure someone as resourceful as yourself could at least drain a few bank accounts before anyone on my team grows suspicious."

"Hmm. Tempting," he mused. "And it is a little poetic to trap you in here in place of me..."

"Precisely," Helen said, swallowing. "Face it, Adam. You're not going to get out of here unnoticed. With me you have the best chance and the most time. Do we have a deal?"

"No, Helen, please." Nikola's voice was shaking, barely audible. "Just – just let him have me, alright? Don't do this."

"I'm sorry, Nikola," Helen said. She didn't trust herself to look at him.

"Still…" Adam narrowed his eyes at her, and Helen abruptly remembered that he had all of Nikola's memories. Nikola, who knew her better than anyone else alive. She held his gaze, praying that he wouldn't see through her.

"A little more poetic to trap you both here together, don't you think?" he said suddenly, and grinned Nikola's wide grin.

"Adam!" Helen shouted at the same time as Nikola.

He raised his eyebrows. "Bye bye, kiddies. Don't have too much fun now!"

With that, he disappeared.

"Hey, get back here! I wasn't done insulting you!" Nikola seethed. "That little digital bastard. When I get out of here – " He stopped, and his expression changed.

"He can only take one of our bodies," he said. "One of us can still get out. Helen…"

She knew exactly what he was about to offer, and before he could, she turned to face him completely, letting him see her expression.

"Turn on the webcams, Nikola," she told him, her lips quirking.

He waved his hand, keeping his eyes locked on hers. The outside cameras dropped into their field of view. On them could be seen both of their bodies in what looked like one of the largest Sanctuary cells – and Helen's was strapped down just as his was, with her entire team hovering expectantly around it. But it was the device clutched in Will's hand and the small mechanical spider on a table nearby that caught Nikola's attention.

Helen watched a slow, disbelieving smile creep over his face as he figured out her plan. "Oh Helen," he breathed. "Have I mentioned lately that – "

"Let me guess," Helen said. "I'm hot when I'm brilliant?"

"I was going to say devious, but sure, that works." Nikola continued staring at the cameras. "Wolf-boy must have had quite a time uploading your consciousness separately without Adam noticing."

"It wasn't easy," she said. "But it appears he succeeded."

"Well done, Henry," Nikola said absently.

"Maybe you should tell him that, when we get out of here," Helen said.

"Hmm." Nikola took another look at the scene. "I notice young Wilhelm is doing the honors."

Helen followed his eyes with a pang. Henry was the one who understood the Praxian technology best, but…

"I couldn't force Henry to do it. He wanted to trap him, like we did last time. Like Professor Moriarty, he told me," she said with a faint, sad smile.

But Adam's program was so distorted – he didn't remotely resemble even the man he used to be. He seemed to be nothing now but pure hatred. He'd escaped them once; she couldn't take the chance of letting him out into the world. So it fell to Will, her second in command.

Helen had known Adam wasn't going to fall for the same switch they'd pulled last time. This time, he'd make sure it was a real live body he was transferring his program into.

Of course, since their move to Hollow Earth, they had acquired the technology for Henry to engineer not only a device to reverse Praxian brain-death, but to cause it. And Adam's brain was the only part of him they had to worry about.

All Helen had needed to do was bluff.

Looking back at the cameras, Helen could read the conflict on Will's face as clearly as if she were in the room with him. He was no fonder of Adam than she was, but what she was asking him to do was hard no matter the circumstances.

She had to wince when her own eyes opened and there was Adam, struggling against the bonds and shouting something she was grateful she couldn't hear. Her team recoiled slightly, Henry especially looking stricken, and Will's hand tightened on the device. He hesitated, only for a split second, before acting.

It was an odd sensation to watch herself flatline – knowing that it was Adam instead of her only made it more bizarre. Helen felt a chill run through her. She looked over to find Nikola watching her. (And, she noticed, carefully averting his eyes from the screen.)

"Seems kinda anticlimactic, doesn't it?" he asked.

"Not everyone has your sense of the dramatic, you know," Helen said. Still, she understood. Here they were, the last of the Five, looking on while one of their greatest enemies was defeated for the final time…and they didn't even have sound.

They both turned back to the cameras and watched in silence; Nikola's hand found hers, and Helen found herself stroking his warm fingers.

Maybe it was a strangely hollow victory, but Nikola was safe. The Sanctuary was safe, and Adam would never be a threat to anyone again – so Helen would take the victory.

On the screen, Erika checked some of her monitors and gestured at Henry, who nodded and made a beeline for the spider.

"It's done," Helen said. "Time to go home."


	9. Italy

**A/N: And the last chapter is here! Thank you so much for reading!**

* * *

"Helen?"

Helen opened her eyes slowly, grimacing as even the moderate lighting in the Sanctuary pierced through them. She had forgotten just how painful undergoing Praxian brain death was.

She was still sitting in the same chair she had been in when Henry had downloaded her mind into the spider. The restraints they'd used to secure her body had been released. Nikola was balanced next to her, keeping an arm tight around her and apparently determined to be as close as possible even if it looked like he was about to fall off the chair. Henry was crouched on her other side, Erika standing next to him, with Will, Kate, Declan, and Bigfoot all hovering nearby.

"Helen," Nikola repeated softly.

"How are you feeling?" Henry asked.

Helen sat up, stifling a groan. "Fine, thank you, Henry. Is Adam taken care of?"

"Sure is." Henry waved toward the computer. "I wiped the system after we got you guys out, just in case. We shouldn't have to worry about creepy AI ghosts ever again."

"Excellent," Nikola said, sounding less smug than usual.

"Thank you, Henry," Helen said gently.

He gave her a tentative smile. "No problem. At least you're both ok."

Bigfoot nodded.

Helen looked around at all of them standing there smiling, and in spite of everything that had happened, she found herself smiling back.

"Could I get a moment with Nikola, please?" she asked.

"Sure," Henry said, jumping to his feet. "I gotta brew you up some Praxian zombie coffee anyway."

He dashed out as Helen chuckled.

"I'm glad you're alright, Dr. Magnus," Erika said, smiling at Helen before following him.

Will, Kate, and Declan filed out after similar congratulations, leaving Bigfoot only. "Sure you're ok?" he asked her, glancing over at Nikola.

She gave him an encouraging look. "I will be," she assured him, and he nodded, leaving them alone.

As soon as the door closed, Helen let herself lean back, closing her eyes against her splitting headache. Nikola planted a light kiss on her temple.

"Hey, at least it's not real coffee," he pointed out.

She laughed a little. "True. That would be immeasurably worse."

Nikola was quiet for a moment, reaching up to stroke her cheek. "Helen – "

She cut him off, taking his hand. "Nikola. You couldn't have prevented this."

He kissed her hand, his eyes soft, but all he said was, "I was just gonna ask if you wanted some tea to wash it down."

* * *

Over the next few weeks, Nikola didn't say a word more about what happened during his trips through the virtual time loop, or even alter his behavior much outside of an unwillingness to leave Helen's side for more than a few hours at a time, but she knew him well enough that he didn't have to.

She understood; she'd give him all the time he needed. Still, if their positions had been reversed, she knew Nikola would have made it his solemn duty to cheer her up by taking her mind off of things. The least she could do was attempt to return the favor.

Helen knocked on the door of his laboratory before walking in. "Nikola?" she said.

"Yes, my – " Nikola looked up from his computer and cleared his throat. "Hey, Helen."

"Are you working on anything pressing at the moment?" she asked, getting right down to business.

"Apart from keeping your Sanctuary running smoothly and efficiently with my usual stunning brilliance? No. Why?"

Helen smiled slightly. "Do you think Henry could manage without you for a few weeks?"

"Well, you all managed without me for a few years, although I'm sure I have no idea how," Nikola said, leaning back and crossing his arms, his chair rocking a little. "I know that glint in your eye. You have something up your sleeve."

Helen dragged a chair over and sat down opposite him. "You're aware that I go to Italy every seven years."

"Of course. As you well know, because of my continuing efforts to convince you to take more than _one_ vacation every seven years. Come on, Helen. Everybody needs a break sometimes."

"Perhaps," Helen said. "That's hardly relevant right now. My seven years are up again next week."

"Oh," Nikola said. "Well, have fun. Bring a few bottles back for me, will you?"

"It's unlike you to be so deliberately obtuse, Nikola."

"Maybe," Nikola said, directing his attention back to his computer. "Maybe I'm not feeling very like myself at the moment," he added very quietly.

"Which is precisely why I want you to come with me," Helen said, leaning forward and clasping her hands together on his desk.

He looked rather stunned. "You never take anyone with you."

"Come with me," she repeated.

"I'm flattered, Helen, really." He paused. "But I'm not really sure I'll be as much fun as I usually am."

"I don't care," she told him.

He gave her a look, a tiny spark growing in his eyes. "I'll drink all your wine," he warned.

"You're welcome to it."

"You won't get anything done if I come with you."

"Neither will you," Helen pointed out.

"I, uh – I can live with that," Nikola said.

"So can I."

He kept looking at her for a minute before his face split into the brightest smile Helen had seen on him in weeks. It reached all the way to his eyes, crinkling the edges and filling them with the warm light she had missed so much lately.

"The neighbors will talk," he said.

"Ah, Nikola," Helen said. "Do you really think I care?"

He grinned. "When do we leave?"


End file.
